4D55 Maintenance

[coyotefiveoh]

Hello, My name is Jeremy.

Just recently acquired a 1986 Ranger with a 4D55 factory turbo diesel engine. I am fairly new to the diesel world so be easy on me ;)

Looking for maintenance procedures so i can keep this baby running for a long time.

Any tips/how-to's to keep her running great?

Starts awesome, flashes right up, has a little knocking when it is cold and goes pretty quiet when it warms up. Also, my fuel economy does not seem to be as great as some have been saying. I am only getting about 20MPG and from what i have read, i should be in the high 20's low 30's so just looking for some info so I can get a little better mileage! :) Have read that worn injectors or bad valves/out of adjustment valves could be a cause? So i should check those, what about a How-to on adjusting valves on a diesel and a good place to get injectors rebuild? I am located in British Columbia, Canada, and could ship them out to get rebuilt if needed or take them to a place close to me!

I have downloaded the service manuals listed on this site, maybe im just blind, but i dont see any maintenance procedures in the manuals.

Love to get any information you guys have available, i have been looking around on the site and it seems like there is quite a bit of knowledge to be learned! :)

Thanks!

[coyotefiveoh]

Ok, i found maintenance procedures in the downloaded manuals.

So Valve clearance should be .25 if i am correct?
#1 Piston @ TDC, Both valves should be open or closed? (springs loose?) and only certain valves as a time. (cannot remember which ones but its listed in manual)

Confirmation would be great! thanks!

[Wardcolorado]

The way I was taught to do it is start with valve 1, cylinder 1. Turn the crank (with a ratchet) till the valve is fully open (spring compressed) -- this is pretty easy to see, the rocker on the pointiest part of the cam lobe. Make a mark on the crankshaft. Turn the crankshaft exactly one revolution -- this will make the camshaft turn exactly half a revolution, so it will be exactly opposite the cam lobe. Adjust that valve to the proper clearance (I cannot remember exactly what it is right now). Then do the same procedure with valve 2, cylinder 1, and so on, till you do it with all eight valves.

The advantage of this, according to the guy who taught me (he's been doing it since the early 60's), is that it doesn't matter what the cam timing or cam profile or whatnot is -- you are finding the exact opposite of the top of each lobe, to make sure the valve is as fully closed as it gets, rather than trying to determine TDC for different pistons and worrying whether cam timing is offset from crank timing or what.

[coyotefiveoh]

makes 100% sense, ill get to it and let you know how it goes, wont be right away but just preparing :) thanks!

[coyotefiveoh]

should i take off all the belts to make it easier to spin crank?? i would think so....?

[Wardcolorado]

I didn't. The fan is what really gets in the way of getting a socket on it and getting your hand down there to operate the ratchet.

Z